package com.wc.AlgoOJ_homework.AlgoOJ_test7.E_做任务;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.StringTokenizer;

/**
 * @Author congge
 * @Date 2024/3/25 19:28
 * @description http://43.138.190.70:8888/p/743?tid=65f90350f9a80dc9ddc3f0f3
 */
public class Main {
    static FastReader sc = new FastReader();
    static PrintWriter out = new PrintWriter(System.out);
    static int N = 200010;
    static int[] a = new int[N];
    static long[] s = new long[N];
    static int t, n, d;
    static long c;

    public static void main(String[] args) {
        t = sc.nextInt();
        while (t-- > 0) {
            n = sc.nextInt();
            c = sc.nextLong();
            d = sc.nextInt();
            for (int i = 1; i <= n; i++) a[i] = sc.nextInt();
            Arrays.sort(a, 1, n + 1);
            for (int i = n; i >= 1; i--) s[i] += s[i - 1] + a[i];
            long sum = 0;
            for (int i = n, j = 1; i >= 1 && j <= d; i--, j++) {
                sum += a[i];
            }
            // 前d天就可以满足,就不用啦,后面就是
            if (sum >= c) {
                out.println("Infinity");
            } else if ((long) a[n] * d < c) {
                out.println("Impossible");
            } else {
                int l = 0, r = d;
                while (l < r) {
                    int mid = l + r + 1 >> 1;
                    if (check(mid)) l = mid;
                    else r = mid - 1;
                }
                out.println(r);
            }
            Arrays.fill(s, 1, n + 1, 0);
        }
        out.flush();
    }

    static boolean check(int mid) {
        if (mid == 0) return true;
        long res = 0;
        int i, j;

        // j至少大于最小轮子的个数
        for (i = n, j = d; i >= 1 && j >= d / (mid + 1); i--) {
            res += (long) a[i] * (d / (mid + 1));
            j -= d / (mid + 1);
        }

        // 剩下的最后一轮走
        j = d - d / (mid + 1) * (mid + 1);
        for (i = n; i >= 1 && j > 0; i--, j--) {
            res += a[i];
        }
        return res >= c;
    }
}

class FastReader {
    StringTokenizer st;
    BufferedReader br;

    FastReader() {
        br = new BufferedReader(new InputStreamReader(System.in));
    }

    String next() {
        while (st == null || !st.hasMoreElements()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }

    int nextInt() {
        return Integer.parseInt(next());
    }

    String nextLine() {
        String s = "";
        try {
            s = br.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return s;
    }

    long nextLong() {
        return Long.parseLong(next());
    }

    double nextDouble() {
        return Double.parseDouble(next());
    }

    // 是否由下一个
    boolean hasNext() {
        while (st == null || !st.hasMoreTokens()) {
            try {
                String line = br.readLine();
                if (line == null)
                    return false;
                st = new StringTokenizer(line);
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return true;
    }
}
